HIV drug resistance in Africa: an emerging problem that deserves urgent attention

HIV-1 diversity and pre-treatment drug resistance in the era of integrase inhibitor among newly diagnosed ART-naïve adult patients in Luanda, Angola

The surveillance of drug resistance in the HIV-1 naïve population remains critical to optimizing the effectiveness of antiretroviral therapy (ART), mainly in the era of integrase strand transfer inhibitor (INSTI) regimens. Currently, there is no data regarding resistance to INSTI in Angola since Dolutegravir-DTG was included in the first-line ART regimen. Herein, we investigated the HIV-1 genetic diversity and pretreatment drug resistance (PDR) profile against nucleoside/tide reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), and INSTIs, using a next-generation sequencing (NGS) approach with MinION, established to track and survey DRMs in Angola. This was a cross-sectional study comprising 48 newly HIV-diagnosed patients from Luanda, Angola, screened between March 2022 and May 2023. PR, RT, and IN fragments were sequenced for drug resistance and molecular transmission cluster analysis. A total of 45 out of the 48 plasma samples were successfully sequenced. Of these, 10/45 (22.2%) presented PDR to PIs/NRTIs/NNRTIs. Major mutations for NRTIs (2.2%), NNRTIs (20%), PIs (2.2%), and accessory mutations against INSTIs (13.3%) were detected. No major mutations against INSTIs were detected. M41L (2%) and I85V (2%) mutations were detected for NRTI and PI, respectively. K103N (7%), Y181C (7%), and K101E (7%) mutations were frequently observed in NNRTI. The L74M (9%) accessory mutation was frequently observed in the INSTI class. HIV-1 pure subtypes C (33%), F1 (17%), G (15%), A1 (10%), H (6%), and D (4%), CRF01_AG (4%) were observed, while about 10% were recombinant strains. About 31% of detected HIV-1C sequences were in clusters, suggesting small-scale local transmission chains. No major mutations against integrase inhibitors were detected, supporting the continued use of INSTI in the country. Further studies assessing the HIV-1 epidemiology in the era of INSTI-based ART regimens are needed in Angola.

Temporal dynamics and drivers of durable HIV viral load suppression and persistent high- and low-level viraemia during Universal Test and Treat scale-up in Uganda: a population-based study

INTRODUCTION

Population-level data on durable HIV viral load suppression (VLS) following the implementation of Universal Test and Treat (UTT) in Africa are limited. We assessed trends in durable VLS and viraemia among persons living with HIV in 40 Ugandan communities during the UTT scale-up.

METHODS

In 2015-2020, we measured VLS (<200 RNA copies/ml) among participants in the Rakai Community Cohort Study, a longitudinal population-based HIV surveillance cohort in southern Uganda. Persons with unsuppressed viral loads were characterized as having low-level (200-999 copies/ml) or high-level (≥1000 copies/ml) viraemia. Individual virologic outcomes were assessed over two consecutive RCCS survey visits (i.e. visit-pairs; ∼18-month visit intervals) and classified as durable VLS (<200 copies/ml at both visits), new/renewed VLS (<200 copies/ml at follow-up only), viral rebound (<200 copies/ml at initial visit only) or persistent viraemia (≥200 copies/ml at both visits). Population prevalence of each outcome was assessed over calendar time. Community-level prevalence and individual-level predictors of persistent high-level viraemia were also assessed using multivariable Poisson regression with generalized estimating equations.

RESULTS

Overall, 3080 participants contributed 4604 visit-pairs over three survey rounds. Most visit-pairs (72.4%) exhibited durable VLS, with few (2.5%) experiencing viral rebound. Among those with any viraemia at the initial visit (23.5%, n = 1083), 46.9% remained viraemic through follow-up, 91.3% of which was high-level viraemia. One-fifth (20.8%) of visit-pairs exhibiting persistent high-level viraemia self-reported antiretroviral therapy (ART) use for ≥12 months. Prevalence of persistent high-level viraemia varied substantially across communities and was significantly elevated among young persons aged 15-29 years (vs. 40- to 49-year-olds; adjusted risk ratio [adjRR] = 2.96; 95% confidence interval [95% CI]: 2.21-3.96), males (vs. females; adjRR = 2.40, 95% CI: 1.87-3.07), persons reporting inconsistent condom use with non-marital/casual partners (vs. persons with marital/permanent partners only; adjRR = 1.38, 95% CI: 1.10-1.74) and persons reporting hazardous alcohol use (adjRR = 1.09, 95% CI: 1.03-1.16). The prevalence of persistent high-level viraemia was highest among males <30 years (32.0%).

CONCLUSIONS

Following universal ART provision, most persons living with HIV in south-central Uganda are durably suppressed. Among persons exhibiting any viraemia, nearly half exhibited high-level viraemia for ≥12 months and reported higher-risk behaviours associated with onward HIV transmission. Intensified efforts linking individuals to HIV treatment services could accelerate momentum towards HIV epidemic control.

Temporal dynamics and drivers of durable HIV viral load suppression and persistent high- and low-level viremia during Universal Test and Treat scale-up in Uganda: a population-based study

Introduction

Population-level data on durable HIV viral load suppression (VLS) following implementation of Universal Test and Treat (UTT) in Africa are limited. We assessed trends in durable VLS and viremia among persons living with HIV in 40 Ugandan communities during UTT scale-up.

Methods

In 2015-2020, we measured VLS (defined as <200 RNA copies/mL) among participants in the Rakai Community Cohort Study, a longitudinal population-based HIV surveillance cohort in southern Uganda. Persons with unsuppressed viral loads were characterized as having low-level (200-999 copies/mL) or high-level (≥1,000 copies/mL) viremia. Individual virologic outcomes were assessed over two consecutive RCCS survey visits (i.e., visit-pairs; ∼18 month visit intervals) and classified as durable VLS (<200 copies/mL at both visits), new/renewed VLS (<200 copies/mL at follow-up only), viral rebound (<200 copies/mL at initial visit only), or persistent viremia (<200 copies/mL at neither visit). Population prevalence of each outcome was assessed over calendar time. Community-level prevalence and individual-level predictors of persistent high-level viremia were also assessed using multivariable Poisson regression with generalized estimating equations.

Results

Overall, 3,080 participants contributed 4,604 visit-pairs over three survey rounds. Most visit-pairs (72.4%) exhibited durable VLS, with few (2.5%) experiencing viral rebound. Among those with viremia at the initial visit ( n =1,083), 46.9% maintained viremia through follow-up, 91.3% of which was high-level viremia. One-fifth (20.8%) of visit-pairs exhibiting persistent high-level viremia self-reported antiretroviral therapy (ART) use for ≥12 months. Prevalence of persistent high-level viremia varied substantially across communities and was significantly elevated among young persons aged 15-29 years (versus 40-49-year-olds; adjusted risk ratio [adjRR]=2.96; 95% confidence interval [95%CI]:2.21-3.96), men (versus women; adjRR=2.40, 95%CI:1.87-3.07), persons reporting inconsistent condom use with non-marital/casual partners (versus persons with marital/permanent partners only; adjRR=1.38, 95%CI:1.10-1.74), and persons exhibiting hazardous alcohol use (adjRR=1.09, 95%CI:1.03-1.16). The prevalence of persistent high-level viremia was highest among men <30 years (32.0%).

Conclusions

Following universal ART provision, most persons living with HIV in south-central Uganda are durably suppressed. Among persons exhibiting viremia, nearly half maintain high-level viremia for ≥12 months and report higher-risk behaviors associated with onward HIV transmission. Enhanced linkage to HIV care and optimized treatment retention could accelerate momentum towards HIV epidemic control.

Antimicrobial resistance from a One Health perspective in Zambia: a systematic review

BACKGROUND

Antimicrobial resistance (AMR) is widely acknowledged as a global health problem, yet its extent is not well evaluated, especially in low-middle income countries. It is challenging to promote policies without focusing on healthcare systems at a local level, therefore a baseline assessment of the AMR occurrence is a priority. This study aimed to look at published papers relating to the availability of AMR data in Zambia as a means of establishing an overview of the situation, to help inform future decisions.

METHODS

PubMed, Cochrane Libraries, Medical Journal of Zambia and African Journals Online databases were searched from inception to April 2021 for articles published in English in accordance with the PRISMA guidelines. Retrieval and screening of article was done using a structured search protocol with strict inclusion/exclusion criteria.

RESULTS

A total of 716 articles were retrieved, of which 25 articles met inclusion criteria for final analysis. AMR data was not available for six of the ten provinces of Zambia. Twenty-one different isolates from the human health, animal health and environmental health sectors were tested against 36 antimicrobial agents, across 13 classes of antibiotics. All the studies showed a degree of resistance to more than one class of antimicrobials. Majority of the studies focused on antibiotics, with only three studies (12%) highlighting antiretroviral resistance. Antitubercular drugs were addressed in only five studies (20%). No studies focused on antifungals. The most common organisms tested, across all three sectors, were Staphylococcus aureus, with a diverse range of resistance patterns found; followed by Escherichia coli with a high resistance rate found to cephalosporins (24-100%) and fluoroquinolones (20-100%).

CONCLUSIONS

This review highlights three important findings. Firstly, AMR is understudied in Zambia. Secondly, the level of resistance to commonly prescribed antibiotics is significant across the human, animal, and environmental sectors. Thirdly, this review suggests that improved standardization of antimicrobial susceptibility testing in Zambia could help to better delineate AMR patterns, allow comparisons across different locations and tracking of AMR evolution over time.

Acquired HIV drug resistance among children and adults receiving antiretroviral therapy in Tanzania: a national representative survey protocol

INTRODUCTION

Tanzania is making an enormous effort in scaling-up of antiretroviral therapy (ART). However, people living with HIV (PLHIV) continue to succumb to the challenge of drug resistance. Evidence on drug resistance for a national survey is unavailable in Tanzania. Therefore, we sought to assess viral suppression (vs) rates and magnitude of acquired drug resistance (ADR) among PLHIV.

METHODS AND ANALYSIS

A national survey will be conducted from 26 July to 29 October 2021 in 22 regions, recruiting 2160 participants. These will include adults on ART for 9-15 months and ≥48 months and children on ART for 9-15 months and ≥36 months. A standardised questionnaire will capture participants' demographic and clinical data. Plasma and dried blood spot will be prepared for viral load testing and drug resistance genotyping. Statistical analyses to determine the burden of ADR, characteristics and factors associated therewith will be done using STATA V.15.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the National Health Research Ethics Committee of Tanzania (NIMR/HQ/R.8a/Vol.IX/3432). Appropriate participant informed consent or parental consent and assent will be obtained. Dissemination will include a survey report, conference presentations, policy briefs and peer-reviewed publications.

Short Communication: Nucleoside Reverse Transcriptase Inhibitors with Reduced Predicted Activity Do Not Impair Second-Line Therapy with Lopinavir/Ritonavir or Darunavir/Ritonavir

Second-line therapy randomized trials with lopinavir/ritonavir question the value of resistance testing to guide nucleoside reverse transcriptase inhibitor (NRTI) selection. In this study, we investigated the association between baseline drug resistance and treatment outcome after 104 weeks of second-line therapy with NRTIs and either darunavir/ritonavir or lopinavir/ritonavir in West-central Africa. We did an observational analysis of data from 387 individuals in a randomized, open-label 2LADY trial in Burkina Faso, Cameroon, and Senegal. We modeled the association between RTI drug resistance mutations (DRMs) and virological failure (VF) (viral load [VL] <50 copies/mL) at week 104 using logistic regressions. Covariates included baseline VL and CD4⁺ count, demographic, and adherence data. Overall, 193 (49.9%), 150 (38.8%), and 44 (11.4%) individuals had, respectively, low/none (genotypic susceptibility score [GSS] <1), intermediate (GSS = 1), and high predicted NRTI activity (GSS >1) in their prescribed second-line regimen. The average number of DRMs by drug class, the proportion of individuals by GSS category, and the duration of first-line therapy were not associated with VF (p > .05). High VL at switch was the only consistent prognostic factor for VF after multivariate adjustment (p < .01). Suboptimal adherence, high predicted RTI activity, or low NRTI mutations were associated with VF (p < .05) when using higher end points for VF or in the intention-to-treat analysis. In conclusion, the use of RTIs with predicted reduced activity does not impair second-line protease inhibitor-based therapy. Therefore, HIV care in resource-limited settings should prioritize strategies to improve adherence and targeted VL testing over drug resistance testing for selecting NRTIs during a protease-based second-line switch.